Engine starter



Feb. 13, 1934. c s BURNETT 1,946,481

ENG INE STARTER Filed April 25, 1933 /NVEN TOR BY CH E5 SBUR/VETT ATTORNEY Patented Feb. 13, 1934 PATENT OFFICE ENGINE STARTER Charles S. Burnett, San Francisco, Calif.

Application April 25, 1933. Serial No. 667,826

6 Claims.

(Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 0. G. 757) This invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to an engine starter and more particularly it is directed to a device of this character for automatically connecting a starting motor thereof to a member of the engine to be started and for thereafter transmitting the power thereto for the starting of such engine.

One of the objects of my invention is to provide an engine starter with a mechanism for facilitating the automatic meshing of a driving pinion with a gear of the engine to be started, said mechanism being adapted to initially. align the teeth of said driving pinion in position with the teeth of said gear and cause said driving pinion to move into engagement with said gear for rotation thereof to start such engine together with means for returning said driving pinion to normal inoperative position after the said engine has been started and for preventing said driving pinion from engaging said gear when said engine is running.

Another object of my invention is to provide an engine starter with means for causing the teeth of a starter pinion to mesh with teeth of a flywheel of the engine to be started in such a manner as to prevent engagement under a heavy blow and further will effect engagement thereof without end thrust of tooth against tooth, thereby preventing breakage and noisy clashing operation.

Still another object of my invention is to provide an engine starter which is simple in operation, inexpensive to manufacture, positive in action and which is not liable to get out of order.

With the above and other objects and advantages in view, the invention specifically consists in features of construction, arrangement and operation of parts which will hereinafter appear. For purposes of illustration the invention will be described and claimed with referenceto the accompanying drawing in which like members distinguish like parts and in which- Fig. 1 is a diagrammatic elevation of my improved starter applied to a gear of the engine to be started.

Fig. 2 is a cross-sectional view thereof, taken on line 22 of Fig; 1, but on a larger scale.

Fig. 3 is a longitudinal vertical sectional view thereof, taken on line 33 of Fig. 2, but on a larger scale.

Fig. 4' is a cross-sectional view thereof, taken on line 4-4of Fig. 1, and

Fig. 5 is a perspective view with parts broken away of a mechanism used in carrying out my invention.

My invention is characterized by a starting motor provided with a screw shaft, a driving pinion mounted on said screw shaft, a fixed shaft and a control pinion mounted on the fixed shaft. The control pinion is provided with means which are adapted to cooperate with ratchet teeth provided on the main drive gearof'the engine to be started for controlling the operation or rotation of the control pinion, the said control pinion being permanently in mesh with the driving pinion and adapted to initially and longitudinally align the teeth of the driving pinion in position with the main teeth of the drive gear of the engine and m; cause the driving pinion to be moved longitudinally on the screw shaft for engaging the drive gear of the engine to be started. Means for returning said driving pinion to normal inoperative position after the gear has been rotated and for 15 preventing said driving pinion from engaging said gear when in running motion is also in cluded Within the scope of my invention. If desired the mechanism provided on the control pinion for controlling the operation thereof may be designed to govern the operation of the control pinion at a given speed of the engine to be started for giving the starting motor time to accommodate itself to an electrical impulse before receiving the maximum mechanical load of turn- 55 ingthe engine to be started.

In the illustrative embodiment characterizing my invention theusual starting motor 1 is provided which is suitably connected to a source of current 2 by conductors 3 having a cut-out 4 in 9- 1 circuit therewith. The starting motor 1 is provided with a rotatable screw shaft 5 which extends outwardly from said motor. The free end of'the shaft 5 is rounded and is journalled in a sleeve. or bearing 6 which is connected to the housing 7 of the engine to be started by any suitable means such as by rivets 8. The sleeve 6'is provided with ball-bearings 9 against which the rounded end of the screw shaft 5 is adapted to abut and rotate thereon. The ball-bearings 9 are 10 provided for taking up the end thrust of the screw shaft 5 when the starter is in operation. The shaft 5 is provided with a driving pinion l0 having teethll and also with an interference compression spring 12. The driving pinion 10 is screw m5 threaded on the shaft 5 and is provided for engaging the teeth 13 of a drive gear of a flywheel 14 of the engine to be started. The gear or flywheel 14 is provided with a flange 15 having ratchet teeth 16 provided on the inner periphery 1 o thereof. The ratchet teeth 16 of the flange 15 are of equal number with the teeth 13 of the flywheel; in other words, there is a ratchet tooth 16 for each tooth 13 of the flywheel. The interference spring 12 is made preferably in the form of a coil and is loosely mounted on the forward end. of the screw shaft 5. One end of the interference spring 12 is fitted into the sleeve or bearing 6, while the other end thereof is adapted to abut against the forward face of the driving pinion 10. In order to cause the driving pinion 10 to be advanced longitudinally along the screw shaft 5 with the teeth 11 thereof in aligned position with the teeth 13 of the flywheel 14, an auxiliary or control pinion 17 having teeth 18 is provided. The control pinion is rotatably mounted on a fixed shaft 19 and is adapted to remain permanently in mesh with the driving pinion 10. The shaft 19 is affixed by one end 19 thereof to a portion of the engine (not shown) and extends in a horizontal direction parallel to the rotatable screw shaft 5 into the interior of the flywheel 14. The control pinion 17 is provided with a pin 20 which is affixed by one end thereof to the forward end of the control pinion 17. The pin 20 extends outwardly to within the inner periphery of the flange 15 of the flywheel. The free end of the pin 20 is provided with a pawl 21 which is pivotably connected by one end thereto. The free end of the pawl 21 is adapted to engage the ratchet teeth 16 of the flange 15 for holding the control pinion 17 in operative or stationary position. The fixed shaft 19 is provided with a transverse groove 22 of a substantial j convex shape on the upper peripheral surface thereof and a plurality of equally spaced wells 23 on its lower peripheral surface in line with the groove 22. The groove 22 provides a seat in which an upper portion of a ring 24 may be movably fitted. The eccentric ring 24 is made with a slightly larger diameter than the diameter of the fixed shaft 19 and by seating in the groove 22 is caused to be eccentrically mounted on the fixed shaft 19. The eccentric ring 24 is provided for guiding the pawl 21 of the control pinion 17 and cause the free end thereof to engage with the ratchet teeth 16 of the flange 15 provided on the flywheel 14 for holding the control pinion 17 in operative or stationary position.

The lower peripheral portion of the eccentric ring 24 is provided with a plurality of inwardly projecting spaced screws 25 which are preferably countersunk. Mounted on each of the screws 25 is a coil spring 26. One end of each of the springs 26 is adapted to abut against the inner periphery of the eccentric ring 24, while the other end thereof is adapted to seat in the wells 23 in the shaft 19. These springs 26 permit the ring 24 to move toward a concentric position in relation to the fixed shaft 19 when required. A pin 27 is provided on the control pinion 17 for limiting the outward swing of the pawl 21. The fixed shaft 19 may be provided with a head cap 28. The teeth 18 of the control pinion 17 and the teeth 11.0f the driving pinion 12, together with the teeth 13 of the flywheel 14, have the same pitch.

In operation my improved engine starter functions as follows. Assuming that the gear or flywheel 14 of the engine to be started is at rest and the motor 1 has been started and also that the control pinion 17 is in such a position as to cause the pawl 21 provided thereon to be disengaged from the ratchet teeth 16 on the flywheel 14. With the screw shaft 5 rotating in a counter-clockwise direction, the driving pinion 10 is caused to be rotated therewith which in turn causes the control pinion 17 which is rotatably mounted on the fixed shaft 19 and in mesh with the driving pinion 10 to rotate in a clockwise direction. The control pinion 17 will rotate until the free end of the pawl 21 provided on the pin 20 engages with one of the ratchet teeth 16 of the flange 15 provided on the flywheel and due to the inertia of the flywheel the control pinion 17 is brought to rest, or in other words, is caused to stop rotating with the teeth 18 thereof in operative or aligned position with the teeth 13 of the flywheel 14 thereby causing the teeth 11 of the driving pinion 10 to also be in aligned position with the teeth 13 of said flywheel. By the stopping of the rotation of the control pinion 17 the driving pinion 10 is thereby caused to stop rotating and due to the driving pinion 10 being screw-threaded on the shaft 5, and in mesh with the control pinion 17 it is caused to be automatically moved longitudinally on the shaft 5 against the spring action of the interference spring 12 to contact with the teeth 13 of the flywheel 14. It then continues in a forward direction until the resistance spring 12 obtains a predetermining pressure, whereupon it begins to rotate the flywheel 14. After the engine has been started the interference or compression spring 12 returns the driving pinion 10 to normal inoperative position. The said interference spring 12 being of a sufflcient strength to hold the driving pinion 10 in inoperative position while the engine to be started is running. The pawl 21 is caused to be disengaged from the ratchet teeth 16 of the flange 15 provided on the flywheel by virtue of the flywheel 14 rotating in the same direction as the control pinion 17. Should the speed of the flywheel 14 be such, after having been started by the driving pinion 10 as to be overtaken by the speed of the control pinion 17, the pawl 21 provided on the control pinion 17 will engage the ratchet teeth 16 of the flywheel and cause the driving pinion to move forward longitudinally on the screw shaft 5 against the action of the interference spring 12 into engagement with the flywheel. This engagement of the driving pinion 10 with the rotating flywheel 14 .will be so timed, however, as to cause the teeth 11 of the driving pinion 10 to properly register with the teeth 13 of the flywheel and thereby prevent clashing and breakage of the teeth.

In case the driving pinion 10 is rotating the flywheel 14 of the engine to be started and the control pinion 17 is rotating at the same time therewith, should the speed of the flywheel exceed the speed of the control pinion 17, such as may happen when the engine first starts, the pawl 21 provided on the control pinion 17 will not be damaged if struck by the ratchet teeth 16 of the flange 15 because of the cushioning springs 26 which allow the eccentric ring 24 to move toward a concentric position with relation to the fixed shaft 19.

It will thus be seen that I have provided an engine starter which will afford a positive and safe mechanism for starting an engine, thereby preventing accidents or failures due to breakage or wedging of gears and which is fully automatic in operation. Even though I have herein disclosed my invention as comprising certain features of construction, arrangement and operation, it is nevertheless to be understood that changes may be made therein without departing from the spirit or scope of my invention.

Having disclosed my invention, what I claim as new and useful is:

1. In an engine starter, a drive gear on the engine to be started, a shaft, a pinion mounted on said shaft and adapted to be moved into and out of engagement with said drive gear, means for normally holding said pinion out of engagement with said gear, means for moving said pinion into engagement with said gear when starting said engine, and a mechanism automatically setting the teeth of said pinion in alignment with the teeth of said gear prior to engagement thereof with said gear, said mechanism including a control pinion meshing with said first named pinion and means for controlling the operation of said control pinion.

2. In an engine starter, a drive gear on the engine to be started, auxiliary teeth provided on said drive gear, a shaft, a pinion mounted on said shaft and adapted to be moved into and out of engagement with said drive gear, means for normally holding said pinion out of engagement with said drive gear, means for moving said pinion into engagement with said gear when starting said engine, and a mechanism automatically setting the teeth of said pinion in alignment with the main teeth of said gear prior to engagement thereof with the said gear, said mechanism including a shaft, a control pinion rotatably mounted on said last-mentioned shaft and means on said control pinion adapted to cooperate with the said auxiliary teeth provided on said drive gear for controlling the operation of said control pinion.

3. In an engine starter, a drive gear including ratchet teeth on the engine to be started, a shaft, a pinion mounted on said shaft and adapted to be moved into and out of engagement with said drive gear, means for normally holding said pinion out of engagement with said drive gear, means for moving said pinion into engagement with said gear when starting said engine and a mechanism automatically setting the teeth of said pinion in alignment with the main teeth of said gear prior to engagement thereof with the said drive gear, said mechanism including a shaft, a control pinion mounted on said lastmentioned shaft, and a pawl provided on said control pinion adapted to engage the ratchet teeth on said drive gear for controlling the operation of said control pinion.

4. In an engine starter, a drive gear of the engine in the starter, said drive gear including ratchet teeth provided thereon, a screw shaft, a pinion screw-threaded on said shaft and adapted to be moved into and out of engagement with said drive gear, means for normally holding said pinion out of engagement with said drive gear, a mechanism for automatically setting the teeth of said pinion in alignment with the main teeth of said drive gear prior to engagement thereof with the said drive gear and cause said pinion to be moved into engagement with said drive gear when starting said engine, said mechanism including a fixed shaft, a control pinion rotatably mounted on said fixed shaft, a pawl provided on said control pinion and adapted to engage the said ratchet teeth provided on said drive gear, and means on said fixed shaft for guiding the said pawl into engagement with said ratchet teeth.

5. In an engine starter, a drive gear of the engine in the starter, said drive gear including ratchet teeth provided thereon, a screw shaft, a pinion screw-threaded on said shaft and adapted to be moved into and out of engagement with said drive gear, means for normally holding said pinion out of engagement with said drive gear, a mechanism for automatically setting the teeth of said pinion in alignment with the main teeth of said drive gear prior to engagement thereof with the said drive gear and cause said pinion to be moved into engagement with said drive gear when starting said engine, said mechanism including a fixed shaft, a control pinion rotatably mounted on said fixed shaft, a pawl provided on said control pinion and adapted to engage the said ratchet teeth on said drive gear, means on said fixed shaft for guiding the said pawl into engagement with said ratchet teeth, said means comprising a ring eccentrically mounted on said fixed shaft.

6. A drive gear, a driven gear, spring means for normally holding said gears out of mesh with each other and a mechanism for bringing said gears in mesh with each other, said mechanism including a control pinion in mesh with said drive gear for automatically aligning the teeth of said drive gear with the teeth of said driven gear prior to the said gears being meshed.

CHARLES S. BURNETT. 

